The present invention relates to ultrasonic level and/or concentration sensors.
Ultrasonic transducers can be used to measure a distance to the surface of a liquid. In some situations, a transducer is positioned at the top of a tank for a liquid. In many circumstances, the tank of interest is a liquid tank (for example, a fuel tank) of an automobile, truck, or other vehicle. An ultrasonic signal is generated by the transducer and the time it takes for the signal to travel from the transducer at the top of the tank to the surface of the liquid, reflect off the surface of the liquid, and return to the transducer is measured. If certain information about the tank is known, such as its volume or dimensions, the time measurement can be used in a calculation to determine how much liquid is in the tank.